Theconvenienceand thequalityof the recent f/2.8 Mark II zooms in the range of 16-200 mm changed my shooting style,and on the 5D III body I do not miss the fast primes any more... The DOF difference between the f/2.8 and f/1.4 lenses at a given distance is not huge anyhow, so with f/2.8 I can blur the background nicely in most of the cases, too, if that is my objective....

First of all, I'm sure you meant 160-200mm.

Secondly there is a HUGE DOF difference beetween f2.8 vs f1.4. At longer focal range (160-200mm like you stated), f2.8 does blur the background nicely. However not everyone shoots the way you do....

When say you use a 35mm or 50mm lens, the dof difference and 'blurring ability' between f2.8 and f1.4 is massive!